Automatic spark advancer.



PATENTBD A111113, 1907.

B. P. CHURCHILL. AUTOMATIC SPARK ADVANCER.

APPLICATION I'ILIII)A JULY 28. 1908.

` YUNITED' STATES PATENT :OFFICE RETTA' PIERCE DAVENPORT /AND -EVERETTJ'Q' VROCKWELL, OF

CHICAGO, ILLINOIS.

' AUTOIMIAI'JIC SPARK ADVANCER.4

N6. 'sealer Toall whom it may concrn:

Be it known that l, BENN PITMAN CHURCHILL, a citizen ofthe United States, residing at Milwaukee, in the county of Milwaukee and State of Wisconsin, have invented a certain new and usefullmprovement in Automatic Spark-Advancers, of which the following is a specification.

My invention relates tomechanism for controlling sparking apparatus of gas engines ordinarily used upon automobiles.

As is well known, it is essential to the proper o'peration of a gas engine that the gas in the working cylinder be fully exploded at the instant thepiston begins its working stroke, and as it always takes substantially the same amount of time to explode the gas within the cylinder, itis necessary, where the exploding or sparking is affected by the revolution of a wheel or other corresponding part within the enginemechanism, to cause such revolving mechanism to operate the .sparking mechanism at a considerable earlier point in its revolution than is necessary when the engine is running slower. In otherwords; it is necessary to advance the point of spark. v

The object of my4 invention is to provide automatic mechanism by means of which the point of spark is adv vanced a proper amount as the speed of the engine iiicreases, and is varied asfthe speed ofthe engine varies. More in detail, my invention consists in the applical tion of a gover'normechanism adapted to be moved by the varying speed ofthe engine to a pin which operatesv the sparking mechanism, the governing mechanism being so constructed and arranged that this pin is moved backward and forward in a circle about the center of the wheel or shaft which carries it, a suflicient amount so that it operates the sparking mechanism' earlier or later as required.

My invention further consists in details of construcjtionwhich will be hereafter more fully' described and claimed.'

Figure 1 is aside external 'view of the two cylinders of a gas engine, and a transverse sectional detail view of the primary and secondary shafts of said engine, and the mechanism of my invention forsparking one of the above cylinders applied thereto, there beinga duplicate device for the other cylinder located at some convenient point, usually on the opposite side of the two cylinders. Fig. 2 is'a sectional detail view of my preferred mechanism taken on the line 2 2 of Fig. l; Fig. 3 is a corresponding sectional detail view taken 0n the lineY 3-3 of Fig. 1;' Fig. 4'is a detail view showing the position of the governing mechanism when the engine is'running. at full ihead,`and when the parts have traveled from the position of Fig.l l1 through approximately 180 to a point in which the engine is in the act of sparking. While the cylinders ofthe gas engine form no part of Specification of Letters Patent.- Application tiled July 28,1906. Serial No. 328,188,

, Patented Aug. 13, 1907.

the invention here in question, 1 have, in order to show the relation of the lnechanism to thegsas engine, illustrated two gas engine cylinders l0 and 11.' having on their exterior surfaces cooling devices 12, 13 of the ordinary type. These two cylinders are arranged on opposite sides of the primary crank shaft 15 -carrying Within the casing 16 crank-arms and connecting-arms (not shown) connected with pistons (not shown) within the cylinders. A

, On the shaft 15 is a gear wheel 18, having on its circumference gear teeth 19 meshing with other gear teeth 2 0 upon a larger wheel 21 rigidly secured to the secondary shaftV 23 ofthe. engine. Mounted about, ,but independent of this shaft 23 is a stationary casing 25 forming a part of the frame ofthe engine. On one side of this frame 25 and connected thereto by a screw 26, or other suitable means, is a contact 27- to which is rigidly secured one end o f a spring-switch 28. This switch 28 carries upon its opposite end a contact-point 29 adapted to temporarily engage the contact-block 30. This 'contact-,block 30 is insulated from the casing 25 by the insulation 31, or other suitable means, and has connected to it a binding post s2. This binding posi 32 is, in' a gas engine, always connected to a battery or other' source of electrical energy. (not here shown), and is thence connected in the ordinary manner throughan induction coil to one terminal of the sparkplug .within the engine cylinder. The opposite side ofthe spark-plug is always connected to the frame of the engine, so that electricity can travel from said second side of the spark plug back to the block27 and switch 28.

The parts thus described constitute ordinary construction, and, in this form no part of my invention.

In order to cause the switch 28 to move from the position of Fig. l to that of Fig. 4, and in order to cause the moment of sparking to be advanced, as and for the reasons heretofore stated, I add to the mechanism just described that of my invention, which I will now describe. Upon the 4wheel 21', heretofore described, and inside the casing 25, adjacent to the switch 28, but clear of said switch, I' place two pins 34 and 35, equidistant from the center of the secondary shaft 23. Upon the pin 34 I journal a triangular governor weight 38 having extending from it on the opposite side of the pin 34, a short lever arm 39, with the result that this arm and the governor weight form together a lever of the first class pivoted at 34. Similarly, I journal upon the' pin 35 and within the casing 25, another governorweight 40 exactly like the one'38 heretofore described, except that the extension arm is omitted. Upon the arm 39 is a pin 42, a certain distance from the center of the pin 34. Upon the body of the governor weight 40 is a pin 43, a ydistance from the pin 35 equal to the distance of the pin 42 from the pin 34. Both pins- 42 and 43 are, as shown in the drawings, upon the same side los ' revolution of the wheel 21, strike theswitch 28 and move it from the position of Fig. 1 to that of Fig. 4,

afterpassing which point the spring switch 28 moves back to the positioniof Fig I.

Upon the wheel 2l I provide two stops 47l and 48 adapted to limit the motion ofthe governor weight 38,

and in corresponding positions upon the wheel I provide two other stops 49 and 50 adapted toIimitthe" motion oi the governor weight 40.- Connected to the governor weights 38 and'40 are suitable springs 52 and v 53 adapted to hold said weights in the normal position shown in Fig. l.

In the operation of the mechanism, assume that the parts are as shown in Fig. 1, in which position the engine starts from rest and moves slowly. T he 'contact pin will7 during rotation at this'speed, becarried around in a circle by the wheel 21, andwill, every` time it strikes the spring switch 28, move Vit to the position of Fig. 4, thereby exploding :gas `Within the engine cylinder. As, now, the speed ofthe engine is accelerated, the governor weights 38 and 39 are, in the well-known manner, moved outward from the .position 'of Fig. 2 toward that of Fig. 4, .against the .action of springs 52 and 53. This motion of the governor weights tends to move the pin 45 clockwise in the -arc of a circle about the center of the wheel 2l. Or, in other words, to angularly advance it with reference to a fixed point upon the circumference of the wheel 21', so that as the wheel revolves, it contacts with the spring switch 28 sooner in the revolution oi the wheel'2l than it does when the parts are in the position of Fig. l. When this outward motion oi the governor weights has reached its maximum,` or the position ofFig. 4, this contact-pin 45 is advanced as much as possible, and as much as is necessary for the proper operation of the engine. When, now, the engineA begins to slow down, the governor weights begin vto move backward under the action of the springs 52 and 53, from the position ofFig. 4 to thatof Fig. l, with the result that the contact-pin ,45 is withdrawn or retracted from this advanced position a' vproper amount to give the -engine the proper sparking point for the speed at which the engine is then running.

Having thus described my invention, what I claim as new and desire to secure by Letters-Patent iszi 1. In a gas engine, the combination of a rotating member, a switch connected with the sparking mechanism of the' engine, a governor weight movable with reference to the rotating member, a link connected to said governor, extending along one side of the center of the rotating member, a contact mounted on the link adapted to engage the switch, means for so guiding said link that as the governor Weight moves it moves said Contact on the link about the Center of the rotating member for the purposes set forth.

` 2. In a gas engine, the combination of a rotating memher, a switch connected -w-ith the sparking mechanism of the engine, a governor weight pivoted to the rotating member at one side of its center, a link connected to said govrernor, extending along one side of the center of the rotating member, a contact mounted on the link adapted to engage the switch, means for so guiding said link that as the governor weight moves it moves said contact on the link.

in approximately the are of a circle about the center' of the rotating member for the purposes set forth.

In a gas engine, the combination of. a rotating member, a stationary switch connected with the sparking mechanism of theen'gine two governor weights pivoted to the rotating member on opposite sides of its centexyan arm extending from one of said weights, a link connecting said extending arm on one weight and the body of the otherr Weight, spring mechanism holding said Weights in normal position, and a contact member mounted on said link adapt- Aed lto engage said switch, the'whole arranged to operate as described, for the purposes set forth.

3 In witness whereof, I have hereunto subscribed my name in the presenceof two witnesses.

` BENN PITMAN CHURCHILL.

Witnesses HOWARD M. Cox, E. C. RoCKwELL. 

